The aim of this paper is to analyse the potential relationship between flash flood events and convective precipitation in Catalonia, as well as any related trends. The paper starts with an overview of flash floods and their trends in the Mediterranean region, along with their associated factors, followed by the definition of, identification of, and trends in convective precipitation. After this introduction the paper focuses on the north-eastern Iberian Peninsula, for which there is a long-term precipitation series (since 1928) of 1-min precipitation from the Fabra Observatory, as well as a shorter (1996–2011) but more extensive precipitation series (43 rain gauges) of 5-min precipitation. Both series have been used to characterise the degree of convective contribution to rainfall, introducing the β parameter as the ratio between convective precipitation versus total precipitation in any period. Information about flood events was obtained from the INUNGAMA database (a flood database created by the GAMA team), with the aim of finding any potential links to convective precipitation. These flood data were gathered using information on damage where flood is treated as a multifactorial risk, and where any trend or anomaly might have been caused by one or more factors affecting hazard, vulnerability or exposure. Trend analysis has shown an increase in flash flood events. The fact that no trends were detected in terms of extreme values of precipitation on a daily scale, nor on the associated ETCCDI (Expert Team on Climate Change Detection and Indices) extreme index, could point to an increase in vulnerability, an increase in exposure, or changes in land use. However, the summer increase in convective precipitation was concentrated in less torrential events, which could partially explain this positive trend in flash flood events. The β parameter has been also used to characterise the type of flood event according to the features of the precipitation. The highest values correspond to short and local events, usually with daily β values above 0.5, while the minimum threshold of daily β for catastrophic flash floods is 0.31

The 9th HyMeX workshop will take place from 21 to 25 September 2015, in Mykonos Island, Greece. It will be organized by the National Observatory of Athens at Saint-John hotel.

Objectives

The general objectives of the HyMeX workshops are to strengthen the links and knowledge exchange, as well as to foster collaborations within the HyMeX research community. The 9th HyMeX workshop will occur at midterm of the programme. It will be the opportunity to assess the achievements of the programme, both in terms of data collected and science results, against the original objectives of the HyMeX Science Plan (http://www.hymex.org/public/documents/HyMeX_Science_Plan.pdf). Running over 5 days, the programme will consist of plenary sessions with review solicited talks and Science Teams oral and poster sessions with an open call for contributions to present and discuss recent scientific progresses regarding the Mediterranean water cycle. Leer más de esta entrada

The 9th HyMeX workshop will take place from 21 to 25 September 2015, in Mykonos Island, Greece. It will be organized by the National Observatory of Athens at Saint-John hotel.

Objectives

The general objectives of all the HyMeX workshops are to strengthen the links and knowledge exchange, as well as to foster collaborations within the HyMeX community. The 9th HyMeX workshop will occur at mid-term of the programme. It will be the opportunity to assess the achievements of the programme, both in terms of data collected and scientific studies, against the original objectives of the Science Plan. Running over 5 days, the programme will consist of plenary sessions with review solicited talks and Science Teams oral and poster sessions with an open call for contributions to present and discuss recent scientific progresses in the understanding of the Mediterranean water cycle, from multiscale and multidisciplinary approaches. Leer más de esta entrada

Abstract

We analyse the observed climate-driven changes in summer wildfires and their future evolution in a typical Mediterranean environment (NE Spain). By analysing observed climate and fire data from 1970 to 2007, we estimate the response of fire number (NF) and burned area (BA) to climate trends, disentangling the drivers responsible for long-term and interannual changes by means of a parsimonious Multi Linear Regression model (MLR). In the last forty years, the observed NF trend was negative. Here we show that, if improvements in fire management were not taken into account, the warming climate forcing alone would have led to a positive trend in NF. On the other hand, for BA, higher fuel flammability is counterbalanced by the indirect climate effects on fuel structure (i.e. less favourable conditions for fine-fuel availability and fuel connectivity), leading to a slightly negative trend. Driving the fire model with A1B climate change scenarios based on a set of Regional Climate Models from the ENSEMBLES project indicates that increasing temperatures promote a positive trend in NF if no further improvements in fire management are introduced.

The EGU Plinius Conference on Mediterranean Storms was established in 1999 within the framework of the InterdisciplinaryWorking Group on Natural Hazards (IWG-NH) of the former European Geophysical Society (EGS) – since 2002, European Geosciences Union (EGU). Since its advent, the Plinius Conference series has provided a crucial interdisciplinary forum for improving our understanding of hazardous storms over the Mediterranean basin that are capable of producing strong winds, heavy rains, explosive landslides, devastating flash floods and other related extremes. Given the progress both in the understanding of many of the basic scientific aspects of the triggering, growth, maintenance, and physical impacts of Mediterranean storms, as well as in the model prediction concerning storm life cycles and their hazardous impacts, the 11th Plinius Conference encouraged an even greater interdisciplinary participation than in previous editions. This was achieved by continuing to reach out to scientific experts in the fields of meteorology, climatology, hydrology,
and geomorphology, as well as extending the reach into the disciplines of oceanography, sociology, economics, engineering, and the government management sector. Leer más de esta entrada

The contribution presents the database on floods (1981-2010) that is being developed in the framework of HYMEX project and the preliminary results obtained for the NW sector of Mediterranean region. This database contains data on damages and the main hydrometeorological features of each reported event. The study is included in one of the objectives of the Working Group 5, which is a transversal group of the HYMEX project dealing with all the aspects related to societal and ecological impacts of hydrometeorological extremes, as well as their perception and communication processes. One of the main points of the WG5 is the creation of a common database on floods and their societal impact, for the Mediterranean region, as well as its analysis. Although some databases already exist and are frequently consulted, they are mainly focused on “major” catastrophic events. But the Mediterranean region experiences every year a high number of minor flash-floods that, considered in their totality, produce important losses and disruptions of the everyday life. This contribution is focused on North-Eastern Spain, South of Italy and South-East of France and the objective is to include all the floods that have produced damages, although they are not considered as “major” disasters.